Manifold record material and process for making it



April 24, 1951 B. K. GREEN ET AL 2,550,466

MANIFOLD RECORD MATERIAL AND PROCESS FOR MAKING IT Original Filed July 31, 19 48 MANIFOLD RECORD MATERIAL PAPER OR OTHER RECORD MATERIAL WEB.

. FRONT SURFACE COATED PROFUSELY WITH MINUTE SOLID COLOR-REACTANT ADSORB- ENT PARTICLES HELD IN A BINDER FILM.

REAR SURFACE COATED WITH RUPTURABLE FILM PROFUSELY PROVIDED WITH EN- TRAPPED LIQUID DROPLETS 0F ADSORBATE MATERIAL CONTAIN- INC A SUBSTANCE GIVING A DIS- TINCTIVE COLOR WHEN ADSORBED BY THE PARTICLES ON THE FRONT SURFACE OF ANOTHER UNDERLYING SHEET HAVING A FRONT ADSORB- ENT COATING.

INVENTORS BARRETT K. GREEN 8 ROBERT W. SANDBERG THEIR ATTORNEYS Patented Apr. 24, 1951 MANIFOLD RECORD MATERIAL AND PROCESS FOR MAKING IT Barrett K. Green and Robert W. Sandberg, Dayton, Ohio, assignors to The National Cash Register Company, Dayton, Ohio, a corporation of Maryland Original application July a1, 1948, Serial No.

41,756. Divided and this application September 7, 1950, Serial No. 183,531

2 Claims.

This invention relates to manifold record material and to a process for making it, and more particularly pertains to such record material which acts both as a receiving sheet and atransferring sheet and, hence, is suitable for use in a stack or pile wherein an original entry made on the top sheet by impact or pressure is reproduced on the top surface of each under sheet without the necessity of using interleaved transfer sheets.

This application is a division of pending United States application, Serial No. 41,756, filed by applicants herein, on July 31, 1948.

It is, of course, recognized that heretofore it has been possible to transfer from the back of an entry receiving sheet to an under sheet, without the use of interleaved transfer sheets like carbon paper, by simply coating the back of the receiving sheet with a carbon transfer composition or the equivalent. Such a sheet coated on the back with ordinary carbon transfer composition smudges and dirties the under sheets or the operators hands. Moreover, being coated with colored marking materials, ordinarily of dark appearance, such sheets are not attractive.

The novel transfer sheet which is the subject of this invention is smudge-proof and pleasing in appearance, being white on both sides or white'on the receiving side and a pleasing color on the back side, as the material transferred to the under sheet causes color therein only by reason of a ..color reaction between the transferred material and the sensitized receiving surface, producing a distinctively colored mark on the receiving surface without changing the appearance of the back of the sheet from which suchtransfer is made. The receiving surface is such that, although it is sensitized, it may be used as the surface on which the original entry is made by writing, typing or printing.

The color reaction which causes the distinctively colored marks to appear at points of pressure on the under sheets is of the type known as an adsorption color reaction wherein a color reactant material changes color when adsorbed on a suitable adsorbent material, without the presence of any ionizing medium.

The reactant material which changes color is an electron donor aromatic organic compound having a double bond system which is convertible to a more highly polarized conjugated form upon taking part in an electron acceptor-donor surface chemical reaction, giving it a distinctive color, and the adsorbent material is an inorganic substance which is an acid relative to the organic compound so as to be an electron acceptor when 7 in adsorption contact therewith. The adsorbent material is in fine particle form to provide a large 2 adsorbent surface area per unit area of the record material, and the organic compound is carried in a fiuid so it is more readily mobile to make adsorption contact with the adsorbent.

In our co-pending application for United States Letters Patent Serial No. 38,547, filed July 13, 1948, there is disclosed a pressure sensitive record material producing color by the same type of color reactionexcept the record material disclosed therein was coated on one side only with the two color reactants superimposed in proximity but insulated from each other by a pressure rupturable film. Any pressure or blow on such a sheet produces color.

In the present invention the individual sheet is immune to any pressure or impact, it being 7 necessary to bring two such sheets intosuperimposed relation where the back surface of one sheet rests on the front surface of another sheet of the same material before a color reaction can be caused by pressure.

The color reactant on the sensitized receiving surface is the inorganic reactant in small solid particle form profusely dispersed in a binder coating so that the particles are available for contact by the color reactant droplets transferred from the back of the superimposed sheet by pressure. The transfer coating is a rupturable film having profusely dispersed therein small droplets of an inertroily solvent in which the second color reactant is dissolved, said droplets being expelled locally at points of pressure.

Therefore, it is an object of this invention to provide a sheet of record material which has on a front receiving surface a coating containing small solid particles of a first color reactant material and which has on the rear surface a pressure rupturable coating which has profusely dispersed therein minute liquid droplets containing a second color reactant which produces a distinctive color when in contact with the first color reactant, thedroplets being extrudable locally from the coating on pressure being applied so as to come in contact with the receiving front surface of an underlying sheet of the same kind, there to produce a distinctively colored mark.

Another object of th invention is to provide a process for making such record material.

Further objects and objects relating to details and economies of production will definitely appear from the detailed description to follow. The objects of this invention have been attained by the several embodiments thereof described in detail in the following specifications. The invention is clearly defined and pointed out in the appended claims. j

The drawing is a schematic showingon a large 3 scale of a portion of a piece of the novel record material.

The sheet or web used as a base for the coatings preferably is thin paper although other materials of similar utility suitable for writing or printing may be employed.

The sensitized receiving surface of the sheet contains as the active ingredient a material upon which the active ingredient of the liquid droplets received from the bottom of an overlying sheet may be adsorbed, the adsorbate in the liquid and the adsorbent being selected so as to produce a color upon adsorption taking place.

Among the most satisfactory adsorbents from an economic and functional standpoint is magnesium trisilicate. This material may be applied to the sheet by use of a white or colorless binder to give a white surface which will receive ink or other marking fluid as well as being adsorptive with respect to the adsorbate in the liquid received from the rear surface coating of an overlying sheet. Thus, the novel manifold sheet may be used as a top sheet as well as an intermediate or bottom sheet of a stack.

The color reactant adsorbate carried in the rear surface film of the novel manifold sheet is present therein dissolved in minute droplets of an oily, non-evaporable, inert liquid medium, preferably a chlorinated diphenyl and may consist of one or more color reactants such as crystal violet lactone, which is 3,3 bis(p-dimethylaminophenyl) -6-dimethylamino phthalide, having the structure malachite green lactone, which is 3,3 bis(p-dimethylamino-phenyl) phthalide, having the structure (CHmN mom and 3,3 bis(p-diethylaminophenyl) 6-dimethyl amino phthalide, having the structure .manifold sheet disclosed in Barrett K. Greens United States Patent No. 2,374,862 issued on May 1, 1945, which was useful only as an overlying sheet and which was not sensitized to receive data from an overlying sheet. The present improvement provides a record material sheet having the dual features of being sensitized to receive data from an overlying sheet and of transferring it to an under sheet. The novel manifold sheet is smudge-proof on both sides and is not subject to discoloration by handling as the reactants are on opposite sides of the sheet.

In the following examples, there will be described embodiments of this invention by which the objects of the invention have been successfully attained.

Example 1.The following embodiment of this invention constitutes the best mode of applying the principles thereof as contemplated up to the present time and may be considered the preferred embodiment. It comprises a base web of paper, or the like, on one surface of which, called the transfer surface or rear surface, a coating is applied which becomes a solid pressure-rupturable insulating film in which are entrapped a profuse number of minute liquid droplets in which a color reactant substance has been dissolved. These droplets are, on the average, of the order of from 1 to 5 microns in diameter and are spaced apart, on the average, a distance of the order of micron. The preferred thickness of this coating forming the transfer surface, when dry, is of the order of .001 of an inch.

The transfer coating is made by dissolving one part, by weight, of animal gelatin, having an isoelectric point of pH 8 and a jelly strength of 275 grams as measured by the Bloom gelometer, with three parts, by weight of water heated to Fahrenheit.

Into four parts, by weight, of gelatin solution there is dispersed, or emulsified, three parts, by weight, of a solution of crystal violet lactone, which is 3,3 bis(p-dimethylaminophenyl)-6-dimethylamino phthalide, mixed with an equal weight of bis(p-dimethylaminophenyl) methane being known as methylene base and having the structure wa which the by 25 per cent, or more, with the sensitivity thereof.

' The stlution of crystal violetlactone and'methylene base is made by dissolving 1 parts, by weight, of crystal violet lactone and 1 parts, by weight, of methylene base in 97 parts, by

- weight, of chlorinated diphenyl which has a chlorine content averaging 48 per centby weight. This solution is heated to the temperature of the gelatin solution before it is added thereto and emulsified.

allowed to 0001, after reheating to 150 Fahren- I The emulsion is applied while still hot, or if pheric conditionsor byartificial means suchas ahot air blast or;en a heateddrying drum such as is commonly used inpaper coatingmachines. It .is cbnsidered thatac iryi'ng]v under normal. atmo's'phe'ric environment gives a somewhat better terresistance ,to the dried film or coating in H chlorinated diphnyl solution, droplets are. entrapped. {The dried transfer coating is next treated to drive the droplets from the top surface portion o fthe film into the interior of the film so as, in'ieifect, to form a-surface skin thereon. This is accomplished by wetting the surface of-the dried film with waterat room temperature, thatis from 7 0-80.Fahrenheit, which water has added thereto 1 per cent, byweight, of formaldehyde and 0.1 percent, by weight, of a wetting agent such asfdioctyl ester, of sodium sulfosuccinate. The wetting should be allowed to persist for sevcral'minutes followed .by adrying operation in siwi'humi i mosphe i r a mt mperature or'at an;elevatedftemperature as high as 160 Eahrenheit. The surface wetting'may' be acconiplishedi by floating the coated paper on the waterycoated side down, or by'carrying it around a partiall submerged drum with the coated surface facing outwardly.

Onto the front receiving surface of the sheet is coated the adsorbent color reactant material in a binder. In making the adsorbent coating, per cent, by weight, of paper coating starch in water is cooked at 200 Fahrenheit for 15 min utes and cooled to room temperature.

is dispersed in three parts, by weight, of water,

sion is mixed with one part, by weight, of the starch solution. The "resultant mixture is applied to the sheet, at room temperature, in any convenient manner, as by a paper coating machine. This adsorbent coating, when dry,-should have a thickness of about .0005 of an inch.

The coating thickness specified may be varied without interfering sure onto the absorbent surface of another like Sepa rately, 1 part by weight of magnesium trisilicate' 6 G-dimethylaminophenyl phthalide. A reissue jof that patent to correct the name was made, on August 17, 1948, under N0. Re. 23,024.

Example '2.-Another embodiment of the inventionis in the substitution of 1 'parts by weight of crystal violet lactone for the methylene base of Example 1, making3 parts, by weight, of crystal violet lactone. The color produced isthe same as in Example 1. v H

Example 3.Another embodiment of the invention is the use of malachite green lactone, which is 3,3 bis (p-dimethylaminophenyl) phthalide instead of the crystalviolet lactone of Example 2. This provides a substantially white record material giving a greencolor when adsorbed on magnesium trisilicate but it is not as intense as the blue of crystal violet lactone.

Example 4.- Another embodiment of the invention is the use of an equal weight of tetra;

Example 5.-Another embodiment of the invention is the use of an equal weight of 3,3 bis(p diethylaminophenyl) 6 dimethylamino phthalide, in place of the crystal violet lactone of Example 2. This makes a substantially white record material givinga blue color reaction. v

In Examples 1 to 5, inclusive, there may be substituted for the starch a mixture of starch, casein, and a synthetic latex made of butadienestyrene copolymer material. In such a binder when dried with the adsorbent particles therein, the amount of starch should be 7 per cent, the amount of casein should be 1 per cent and the amount of latex should be 7 per cent, all by .after which seven more parts, by. weight, of

cold water and of a part, by weight, of ammomum-hydroxide of 25 Beaum are added. This sheet will produce a dark blue mark, which intensifies on standing, defining sharply the area of applied pressure. The droplet size is so small that the mark appearing'on the adsorbent surface caused by drawing. a lineon :an overlying sheet appears as a continuous line, and not as a series of dots.

The compound crystal violet lactone may be made by the process described in United States Letters Patent No. 2,417,897, issued March 25, 1947, on the application of Clyde S. Adams, although the compound is incorrectly named in that patent as 3,3 bis(p-dimethy1aminophenyl)- casein dispersion is'heated 'on a water bath at 165 Fahrenheit for 15 minutes and then allowed to cool. The latex to be used should contain approximately 45 per cent ofsolids in water. The adsorbent material particles to be used are dispersed in water as set out in Example 1 except the water should contain 0.2 per cent, by weight, of sodium pyrophosphate. To 10 parts, by weight, of the dispersed adsorbent, eliminating the Weight of the water, is added 3.5 parts, by weight, of thefstarch solution, 1.6 parts, by weight, of the latex, and 1 part, by weight, of the casein solution. This binder material is characterized by greater adhesion to the paper and has excellent properties as far as the access of the adsorbent particles to the action of the liquid color reactant droplets expelled thereonto is concerned.

Referring to the drawing, [0 indicates the sensitized receiving surface coating containing the adsorbent color reactant, II indicates the supporting web, such as paper, and I2 indicates the transfer coatin containing the liquid droplets in which the adsorbate color-reactant material is dissolved.

7- fdld record materialdisclosed herein is disclosed in our co-pendi-ng application for U. S. Letters Patent, Serial No. =4-1,757,' filed July :31, 1948, wherein a stack of such sheets "in superimposed relation .is provided for use in making multiple copies through a single impression.

- It i'snnderstooiil that the novel manifold :record material described herein is susceptible "of considerable variations without departing from the spirit of the invention.

'What is claimed is; t

l. -A sensitized record material adapted to be usedin conjunction withother rec'ord-material-of the "same kind, in superimposed relation and faced in the same direction, to form a manifold pack, including a'sheet of material suitable for-a manifold 'record "material base 'web, said sheet having a front receiving surface and a reartransfer'surface; a coating on the-front receiving surface "of thevsheet comprisinga binder containing profuse numbers of minute solid particles of adsorbent material; and a pressure-rupturable coating on the rear transfer surfacehavinguentrapped therein a profuse number of minute liguiddroplets containing a substance which is a'clsorbable on material like theladsorbent particles in the coating on :the front receiving surface and reactant therewith ,on contact toform a distinctive color, recording pressures on th .front receiving surface "through the adsorbent coating .causingrupturemf .the coating on the ,rear transfer surface locallylat the points of pressure there to release (and ,extrudeon the surface of the said ruptured coatingdroplets :of the liquid, there available .''for :adsorption on the receiving surface of an under :sheet to produce adistinctively'colored mark thereon, ztheadsorbent being magnesium trisilieate, and the adsorbable material =being an electron donor aromatic compound having -a double bondsystem :which is convertible to a more highly polarized conjugated form upon taking part in an electron acceptor-donor surface chemical reaction with the adsorbent, giving it a distinctive color. 7

2. A process for making a sensitized record material sheet to be used in conjunctionwith other sheets of record material of the same-kind, in superimposed relation and faced in the same direction to form aynianifold pack, including the steps of coating one side of a sheet of material, suitable for agmanifold web, ,With a film of binde'r material in which is profusely dispersed minute solid particles of anadsorbent materialiwhich is one of two substances which comprises aniad sorben-t and an adsorbate which produce'color in contact; and the step of coating the other side of the sheet with an emulsion having a continuous phase dryable to a pressure-rupturable film and-having a discontinuous phaseof aninert oily liquid containing the adsorbate substance whereby upon drying the discontinuous phase is entrapped in-the film as a profusion oflminut e droplets of liquid which maybe released locally by pressure appliedto the sheet, the adsorbent being magnesium trisilicate, and the adsorbate material being an electron donor aromatic conipound'having a double bond system which is convertible to a more highly; polarized conjugated form upon taking part an electron acceptordonorsurface chemical reaction with the adsorbent, giving it a distinctive color.

-BAR,RETT 1;. GREEN. B T -iSA DB R -No--references cited. 

